// Copyright Vespa.ai. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
#include <vespa/vespalib/testkit/test_kit.h>
#include <vespa/searchlib/fef/termfieldmatchdata.h>
#include <vespa/searchlib/queryeval/searchiterator.h>
#include <vespa/searchlib/queryeval/wand/wand_parts.h>

using namespace search::queryeval;
using search::fef::TermFieldMatchData;
using search::fef::TermFieldMatchDataPosition;

using Term = wand::Term;

struct TestIterator : public SearchIterator
{
    MinMaxPostingInfo  _info;
    int32_t            _termWeight;
    bool               _useInfo;
    TermFieldMatchData _tfmd;
    uint32_t           _unpackDocId;

    using UP = std::unique_ptr<TestIterator>;
    TestIterator(int32_t maxWeight, int32_t termWeight, bool useInfo)
        : _info(0, maxWeight),
          _termWeight(termWeight),
          _useInfo(useInfo),
          _unpackDocId(0)
    {}
    virtual void doSeek(uint32_t docId) override {
        (void) docId;
    }
    virtual void doUnpack(uint32_t docId) override {
        _unpackDocId = docId;
        _tfmd.appendPosition(TermFieldMatchDataPosition(0, 0, _termWeight, 1));
    }
    virtual const PostingInfo *getPostingInfo() const override {
        return (_useInfo ? &_info : NULL);
    }
    static UP create(int32_t maxWeight, int32_t termWeight, bool useInfo) {
        return UP(new TestIterator(maxWeight, termWeight, useInfo));
    }
};

TEST("require that DotProductScorer calculates max score")
{
    TestIterator::UP itr = TestIterator::create(10, 0, true);
    Term term(itr.get(), 5, 0);
    EXPECT_EQUAL(50, wand::DotProductScorer::calculateMaxScore(term));
}

TEST("require that DotProductScorer uses default max weight when not available in search iterator")
{
    TestIterator::UP itr = TestIterator::create(10, 0, false);
    Term term(itr.get(), 5, 0);
    int64_t exp = (int64_t)5 * std::numeric_limits<int32_t>::max();
    EXPECT_EQUAL(exp, wand::DotProductScorer::calculateMaxScore(term));
}

TEST("require that DotProductScorer calculates term score")
{
    TestIterator::UP itr = TestIterator::create(0, 7, false);
    Term term(itr.get(), 5, 0, &itr->_tfmd);
    EXPECT_EQUAL(35, wand::DotProductScorer::calculateScore(term, 11));
    EXPECT_EQUAL(11u, itr->_unpackDocId);
}

TEST_MAIN() { TEST_RUN_ALL(); }